Fix pyfaust fancy idx bug on py2.7.

Now the .exe (nsi installer) when installed with Py2.7 on PATH gives a pyfaust working for both slicing and fancy/vector indexing.

Solve partly issue #105.

wrapper/python/src/FaustCorePy.pyx

@@ -629,8 +629,15 @@ cdef class FaustCore:
             if(isinstance(indices[i], slice)):
                indices[i] = list(range(indices[i].start, indices[i].stop,
                                        indices[i].step))
-        row_indices = np.array(indices[0], dtype=np.uint64)
-        col_indices = np.array(indices[1], dtype=np.uint64)
+        # it's possible that on certain architectures unsigned long int is a
+        # 4-bytes integer
+        # TODO: move to a cross-platform size type (like uint32/64_t from stdlib.h)
+        if(sizeof(unsigned long int) == 8):
+            dtype = np.uint64
+        elif(sizeof(unsigned long int) == 4):
+            dtype = np.uint32
+        row_indices = np.array(indices[0], dtype=dtype)
+        col_indices = np.array(indices[1], dtype=dtype)
         row_indices_view = row_indices
         col_indices_view = col_indices
 #        print("FaustCorePy.fancy_idx(), row_indices=", row_indices, " size=",